Overview
In the past, we followed the concurrency basics of code in swift using libraries like Grand Central Dispatch (GCD) or libdispatch.
Nowadays, we can enforce the basics for concurrency using the async and await keywords.
1. What is Concurrency?
Let’s take an example: we all are familiar with laptops, right? We play games, create documents or write programs, etc. While doing this most people like to listen to music. In short, perform multiple tasks at the same time. In another example, when shops have too many customers then the shopkeeper will do billing and count the number of items packed into bags, and also answer to the other customers for the same. This is an example of concurrency in simple words.
So in technical terms, Concurrency means performing/processing more than one task parallelly at the same time. Also, we can say that allowing multiple pieces of the code to run at the same time.Swift 5.5 onwards, Async/await functions write asynchronous code without using completion handlers to return values.
2. What is Async?
Async stands for asynchronous and can be seen as a method attribute making it clear that a method performs asynchronous work. It provides non-locking functionality to the program.
3. What is Await?
Await is a keyword to be used for calling an asynchronous method. You can see them as a pair of shoes, without one, the other is useless, in swift as one will never go without the other
“Await is awaiting a callback from his buddy async.”
Syntax:
- By adding the async keyword to any function:
func <functionName>() async {
//init function
}- Async can also return a result:
func <functionName>() async -> <Return Type> {
// init function
return <Return Type>
}- Calling async function:
await <functionName> //Return function let data = await <functionName>
Let’s take an example:
func fetchYudizProjects() async -> ClientResponce {
//fetch yudiz projects
return allClientFeedbacks
}
let clients = await fetchYudizProjects()Although, if we want to execute other tasks or functions while the async function is being executed, then we need to put the“async” keyword in front of the variable declaration. In this case, the “await”keyword should be placed before the variable where we are accessing the result of the asynchronous function.
async let clients = fetchYudizProjects() print(await clients)
The syntax for error handling:
- By adding async throws to any function:
func <functionName>() async throws {
//init function
...
}- Async throws can also return a result:
func <functionName>() async throws -> <Return Type> {
// init function
return <Return Type>
}- At the time of calling function:
do {
try await <functionName>
} catch {
//handle errors
}
//Return function
do {
let data = try await <functionName>
} catch {
//handle errors
}
4. Control Flow Cycle
- Synchronize Function:
- Async/Await Function:
Example:
- Before async/await
- After using async-await
Conclusion
The above example of Async/await in swift allows for concurrency, which will improve the readability of complex async code. It eliminates the need for completion closures and calls into multiple async methods. In addition, we get more flexibility into code.
For more information: Check this reference video
You may also like
Integrating AI in Your eCommerce App for Personalization
In the ever-evolving digital landscape with the changing preferences, of modern consumers there come...
Gamification in Healthcare: Benefits, Trends & Examples
Gamification in healthcare apps reveals a new possibility in transforming the patient's journey.
Gamification in Education: The Winning Trio of AR, VR & AI
Relying on conventional techniques for modern-day challenges...
